The present invention relates to a method and associated apparatus for determining positioning relative to utility lines and, in particular, the positioning of mobile groundbreaking equipment.
There are millions of miles of utility lines buried in North America. These utility lines include: electric power lines, telephone lines, water lines, sewer lines, fibre-optic cable lines, natural gas transmission lines, natural gas distribution lines, and utility lines for transporting hazardous liquids. Every year incidents occur in which mobile groundbreaking equipment damage such utility lines.
Statistics kept by the United States Office of Pipeline Safety regarding pipelines indicate that between 1986 and 2001 there were 1286 incidents involving natural gas transmission lines, which killed 58 people, injured 217 people and caused 284 billion dollars in property damage. In that same period there were 2159 incidents involving natural gas distribution lines, which killed 282 people, injured 1264 people and caused 256 billion dollars in property damage. There were also 3034 incidents involving utility lines carrying hazardous liquids which killed 36 people, injured 244 people and caused a further 731 billion dollars in property damage. In order to understand the full impact of such incidents, one would have to also include environmental damage and economic loss as a result of a service disruption.
There have been previous attempts to address this problem, an example of which is U.S. Pat. No. 4,600,356 (Bridges et al 1986) entitled xe2x80x9cUnderground pipeline and cable detector and processxe2x80x9d. The teachings of the Bridges et al reference is to mount on a mechanical digging implement a metal detector capable of detecting underground conductive objects.
There are inherent problems in mounting a metal detector onto a metal machine. This has lead to a search for alternative technologies which will provide a more reliable result and also be capable of locating utility lines which are non-conductive.
What is required is a method and associated apparatus for determining positioning relative to utility lines.
According to one aspect of the present invention there is provided a method for determining positioning relative to utility lines. A first step involves providing a global positioning apparatus. A second step involves providing a processing unit with a display. The processing unit has stored in memory at least one geographical map depicting positioning of at least one utility line. A third step involves transferring data received from the global positioning apparatus to the processing unit and displaying on the display the positioning of the global positioning device relative to the at least one utility line on the at least one geographical map.
According to another aspect of the present invention there is provided an apparatus for determining positioning relative to utility lines. This apparatus includes a global positioning apparatus and a processing unit with a display. The processing unit has stored in memory at least one geographical map depicting positioning of at least one utility line. The processing unit receives data from the global positioning apparatus and displays on the display the positioning of the global positioning apparatus relative to the at least one utility line on the at least one geographical map.
With the method and apparatus, as described above, the accuracy of global positioning is coupled with the accuracy of utility line survey maps to give accurate real time data as to the positioning relative to the utility line. Although beneficial results can be obtained by a foreman walking on foot, it is envisaged that the global positioning apparatus and the processing unit will be mounted right on a mobile machine, so that the operator is always aware of the positioning of the mobile machine relative to the utility lines. It is, of course, preferable that all known utility lines be illustrated at the same time, to avoid any utility lines being damaged during construction. This would involve preparing a composite utility line survey map from individual utility line survey maps and displaying such composite utility line survey map.
Once the basic system is in place, there are a number of enhancements which may be added to the system. Even more beneficial results may be obtained when an operator alarm is in communication with the processing unit. The processing unit can then be programmed to trigger the operator alarm to alert an operator of the mobile machine should the mobile machine venture within a predetermined distance of a utility line.
A further hazard at construction sites is the safety of workers on foot who are working around the mobile machine. There are various alternative measures which can be taken to ensure the safety of such workers. One solution is to provide mobile global positioning apparatus which are carried by workers working in the vicinity of the mobile machine. The processing unit will receive signals from the mobile global positioning apparatus and display on the display the positioning of each worker relative to the mobile machine. An alternative solution is to provide a detector for detecting the presence of a worker within a predetermined distance of the mobile machine. The detector can be linked to the processing unit, with the processing unit being linked to the operator alarm to alert an operator of the presence of the worker. This alternative solution is less accurate as the operator will not know the precise position of the worker, but is a less expensive solution. It can be implemented through a variety of technologies, some of which include an infrared scanner which responds to heat, a visual scanner which responds to shadows, proximity sensors which respond to objects, a transmitter which interrogates a transponder carried by the worker, a transceiver which communicates with a transceiver carried by the worker, or a radio beacon detector which responds to a radio transmitter carried by the worker.
Even more beneficial results may be obtained when the processing unit has stored in memory for display, upon demand, critical data relating to each utility line. This critical data may include information as the nature of the utility line, ie. does it carry natural gas, telephone, or electrical power. The critical data may also include an emergency contact information of an owner of the utility line.
On large projects involving numerous mobile machines it may be desirable to have a central monitoring station. The central monitoring station will monitor the positioning of the mobile machine. The central monitoring station will receiving coordinate data via satellite or wireless communication from the global positioning apparatus mounted on the mobile machine. The central monitoring station will have a central processing unit with a central display. The processing unit will have stored in memory at least one geographical map depicting positioning of at least one utility line. The central monitoring station will receive data from the global positioning apparatus and display on the cental display the positioning of the mobile machine relative to the at least one utility line on the at least one geographical map. Two way communication will be provided between the central monitoring station and the mobile machine, so that the central monitoring station can communicate with the operator of the mobile groundbreaking machine, as required.